Free-Piston Engine Compressor
The free piston engine compressor is a device that utilizes combustion to compress air into a high-pressure supply tank. The device is configured such that the transduction from thermal energy to stored energy, in the form of compressed gas, is efficient relative to other small-scale portable power supply systems. This efficiency is achieved by matching the dynamic load of the compressor to the ideal adiabatic expansion of the hot gas combustion products. Our work shows that a load that is dominated by inertia in the early portion of the power stroke provides a nearly ideally matched load for achieving high thermodynamic efficiency in a heat engine. The device proposed exploits this fact by converting thermal energy into kinetic energy of the free piston, and then utilizes this stored kinetic energy to compress and pump air on the opposite side of the piston toward the end of the stroke.
Images
Video
Combustion Valve
Both Valves
Liquid Piston
Prototype 1
Slow Motion Valve
Silicone Piston
Fatigue Testing
Prototype 0
Posters
- E. J. Barth, J. A. Willhite, C. Yong “Free-Piston Engine Compressor”. NSF Site Visit for the Center for Compact and Efficient Fluid Power (CCEFP), April 28-30, 2009, University of Minnesota, Minneapolis, MN.
- E. J. Barth, J. A. Riofrio, C. Yong, J. A. Willhite, “Free Liquid-Piston Engine Compressor with Separated Combustion Chamber”. Presented at the Center for Compact and Efficient Fluid Power (CCEFP) ERC annual meeting, May 28-30, 2008, Milwaukee School of Engineering (MSOE), Milwaukee, WI.
- E. J. Barth, and C. Yong, “Modeling and Control of the Free Liquid-Piston Engine Compressor”. NSF Site Visit for the Center for Compact and Efficient Fluid Power (CCEFP), February 20, 2008, University of Minnesota, Minneapolis, MN.
- E. J. Barth, J. A. Riofrio, J. A. Willhite, “Free Liquid-Piston Engine Compressor with Separated Combustion Chamber”. NSF Site Visit for the Center for Compact and Efficient Fluid Power (CCEFP), February 20, 2008, University of Minnesota, Minneapolis, MN.
- E. J. Barth and J. A. Riofrio, “Free Liquid-Piston Engine with External Combustion Chamber”. 1st Annual Meeting for the Center for Compact and Efficient Fluid Power, Georgia Institute of Technology, April 2007, Atlanta, GA.
- E. J. Barth and J. A. Riofrio, “Free-Piston Compressor for Portable Fluid Power Systems”. NSF Site Visit for the Center for Compact and Efficient Fluid Power, University of Minnesota, October 2006, Minneapolis, MN.
- E. J. Barth and J. A. Riofrio, “Free-Piston Compressor for Portable Fluid Power Systems”. NSF Proposal Site Visit for the Center for Compact and Efficient Fluid Power, University of Minnesota, November 2005, Minneapolis, MN.
